Some pregame thoughts on the Giants and Cubs, who open a three-game series at AT&T Park tonight: [...] they are 6 ½ behind Chicago, thanks largely to the Cubs’ four-game sweep at Wrigley Field earlier this month. If the Giants were to sweep this series - getting a win tonight from Matt Cain would be a nice opening statement - they’re right back in this race. Recent columns suggest the national media is very much aware of Matt Duffy’s Rookie of the Year candidacy, and some have placed him right at the top. At .262, he’s not likely to match Duffy’s batting average, but he has 20 homers on the season and stands right at the heart of the Cubs’ compelling saga. Soler strained an oblique over the weekend and is on the 15-day disabled list. Baez, who takes one of the most ferocious cuts in the game, was sent to the minors to start the season because of his alarming strikeout numbers. If you’re wondering about Billy McKinney, the A’s No.